Blow-up preventer

ABSTRACT

An apparatus for arresting upward motion of a wireline tool blown up a production pipe by sudden excessive down hole pressure or fluid flow. The apparatus of the invention includes a wedging member having an oblique lower face, a connector member having a generally mating oblique upper face, and means for suspending a wireline tool therefrom. It also includes means for supporting the wedging member within the annulus of the well pipe and means for slidably coupling the wedging member and the connector member, whereby relative convergent motion between the two members moves the members into a braking or wedging attitude. The apparatus also includes means for imparting relative convergent motion to the wedging and connector members when the apparatus is in an unloaded state.

United States Patent Alexander, Jr.

[ BLOW-UP PREVENTER [72] Inventor: Granison T. Alexander, Jr., Houma, La. [73] Assignee: Gem Oil Tool Company, Houma, La. [22] Filed: Nov. 25, 1970 [21] Appl. No.: 92,595

Related US. Application Data [63] Continuation-impart of Ser. No. 31,965, April 27,

1970, Pat. No. 3,602,306.

[52] US. Cl ..166/217 [51] Int. Cl 1 ..E2lb 23/00 [58] Field otSearch ..166/216,217,212, 209

[56] References Cited UNITED STATES PATENTS 1,502,428 7/1924 Getty 166/217 X 1,036,824 8/1912 Gable. .....166/217 X 1,875,583 9/1932 Fox ..166/217 X 2,794,619 6/1957 Lawrence et al ..166/217 X [4 1 June 13, 1972 2,313,369 3/1943 Spencer...... ..166/217X Primary Evaminer-James A. Leppink Attorney-Paul E. Harris, Lee R. Larkin and Marcus L. Thompson ABSTRACT An apparatus for arresting upward motion of a wireline tool blown up a production pipe by sudden excessive down hole pressure or fluid flow. The apparatus of the invention includes a wedging member having an oblique lower face. a connector member having a generally mating oblique upper face, and

2 Claims, 6 Drawing Figures PATENTEBJUH 13 m2 SHEET 10F 2 INVENTUR. Gran/iron Z" A/exanaer, 4i:

ATTOfiA/[V PATENTEBJUH 13 I972 3.669.187

SHEEI 20F 2 Tia WM BLOW-UP PREVENTER CROSS-REFERENCES TO RELATED APPLICATIONS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention generally relates to an apparatus for preventing hazardous ascent of wireline tools suspended within a production pipe. More particularly, this invention relates to an apparatus which will arrest upward movement of a wireline tool caused by a sudden fluid surge below the tool.

2. Description of the Prior Art Heretofore, there has been a need to prevent the sudden blowing up of wireline tools suspended within a well pipe. When performing routine or special wireline work on producing wells which flow by surges, either by gas lifting or naturally, there is always the danger of having the wireline tools blown or kicked up the tubing. When a tool is suddenly blown up, the wireline above the tools will slacken, ball up, kink and usually break, dropping the tools and creating a difficult fishing job.

The devices used to prevent these problems in the prior art have frequently been insensitive to small variations in the bottom hole pressure and have been extremely difficult to use. Certain of the prior art tools displayed the drawback of unnecessarily having a null point or positional relationship between the parts of the tool which will prevent the operation of that tool. Should a sudden surge of fluid be experienced with the prior art tools in this null point configuration, the troublesome blow-up of the wireline tool cannot be prevented.

Difficulties also have been experienced with inoperativeness of certain prior art tools in conditions of total immersion in liquids. When such tools are above the liquid level in a well, a surge necessarily contacted the lower portion of the tool, setting it to the wedged position, as long as it was not in a null point configuration. However, if the tools are below the liquid level in a well, the surging fluid operated to impart equal upward acceleration to all parts of the tool, preventing setting of the braking mechanism.

U.S. Pat. No. 2,897,898 is generally illustrative of the state of the art.

SUMMARY OF THE INVENTION The apparatus of the invention for use with a wireline tool in an annular opening includes a wedging member having an oblique lower face and a connector member having a generally mating upper face which is also oblique to the longitudinal axis of the apparatus. It also includes means for supporting the wedging member within the annular opening for travel of the apparatus therethrough. It also includes means for coupling the wedging member and the connector member, whereby relative convergent motion between the connector member and the wedging member wedges the wedging member between the side of the annular opening and the connector member by sliding movement generally in the direction defined by the intersection of the mating oblique faces of the members. The apparatus also includes means for imparting relative convergent motion to said wedging member and said connector member when the apparatus is in an unloaded state.

BRIEF DESCRIPTION OF THE DRAWING The invention may be further understood by reference to the drawings, in which:

FIG. 1 is a generally schematic central sectional elevation of 70 lit FIG. 3 is a similarly illustrative cross-sectional view of the apparatus as shown in FIG. 1, taken along line 3-3.

FIG. 4 is a schematic rear elevation view of the inventors preferred embodiment of the invention showing the tool in its longitudinally extended or traveling attitude.

FIG. 5 is a schematic side elevation view of the apparatus of FIG. 4 showing the tool in the axially extended attitude.

FIG. 6 is a schematic front elevation view of the embodi' ment of FIGS. 4 and. 5, showing the tool in the axially extended attitude.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I, the apparatus is generally designated by the numeral 10, and includes an upper wedging member II. a lower connector member 30 and an elongated coupler 20 connected therebetween. Wedging member 11 is provided with threads 12 in its uppermost portion for engagement with a supporting wireline. Wedging member 11 is also provided with a central slot 13 (FIG. 3) which receives the upper portion of elongated coupler 20. Friction means in the form of a plurality of lateral projections are located in the lower portion of wedging member 11, which conveniently take the form of teeth 14. Teeth 14 contact the side of a production pipe 50 when the apparatus assumes the wedging position, as shown in FIG. I.

Wedging member 11 also includes a longitudinal slot 16 therealong which receives the upper lateral lug 21 of coupler 20 (FIG. 5). The sliding lug, as embodied by upper lateral lug 21, may be alternatively included in the lower connector member 30 as well. In its lowermost portion, wedging member 11 is provided with an oblique planar face (FIG. 3) which contacts the upper oblique planar face 31 of lower connector member 30 immediately therebelow.

Connector member 30 is provided with threads 32 at its lowermost portion for receiving and supporting a wireline tool or series of tools (not shown). Connector member 30 also includes a central slot 33 (FIGS. 3 and 6) which receives the lower portion of coupler20. Connector member 30 is rotably fastened to coupler by the lower lateral lug 22 of coupler 20 projecting through lateral opening 34 (FIG. 5) in each side of connector member 30. Upper lateral lug 21 and lower lateral lug 22 are held in the body of coupler 20 by lock pins or an appropriate weld.

Connector member is also provided with an external guard for teeth 14 in the form of guard 35 extending laterally of connector member 30. Guard 35 prevents excessive wear to teeth 14 when the tool is in the axially extended or traveling attitude. When the tool is moved to the wedging attitude, teeth 14 project beyond guard 35 and engage the wall of pipe to cease the ascent of the tool.

Also joining coupler 20 and wedging member 11 is means for imparting relative convergent motion to connector member 30 and wedging member 11, which means takes the form of a spring 17 connected at its upper end to pin 18 within wedging member 11 and at its lower end to pin 24 in coupler 20. Spring 17 is preferably a low-strength spring, on the order of eight pounds pull being necessary to fully extend spring 17 and bring preventer 10 into longitudinal alignment. However, any strength spring may be used so long as the pull exerted by the tools suspended beneath preventer 10 is sufficient to extend spring 17 and bring preventer 10 into longitudinal alignment. The spring urges connector member 30 and wedging member 11 into the longitudinally misaligned or wedging attitude when preventer 10 is in an unloaded state.

An unloaded state is defined as that condition when the effective weight of the tools suspended by preventer 10 is less than the pull of spring 17 urging wedging member 11 and connector member 30 to a relative convergent motion. This condition may occur when preventer 10 is completely submerged in liquid within pipe 50. As the liquid within pipe 50 surges upward, the upward acceleration of wedging member 1 1 and connector member 30 may be substantially equal. Without spring 17 interposed, between wedging member 11 and coupler 20, it is possible that preventer could not be brought into the wedging attitude by the action of the liquid alone. With spring 17 urging wedging member 11 and connector member 30 toward each other in the unloaded state, however, preventer 10 will rapidly assume the longitudinally misaligned, or wedging attitude to cease the ascent of the wireline tools.

Preventer 10 is intended for use within a production pipe 50, or the like, and it preferably inserted between the wireline and a wireline tool to be lowered down production pipe 50. The preferred embodiment of the invention is used in conjunction with a conventional jar, such as a link jar, immediately above the apparatus for dislodging it from the wedged position. This preferred position of the wireline tool, however, is not critical. It may be inserted above the blow-up preventer, as long as there is sufficient weight on connector member 30 to bias spring 17 and keep the tool in the longitudinally extended, or aligned attitude, for travel through the pipe. Both while being lowered down the production pipe and being raised back up the pipe by the wireline, the tool assumes a running or traveling position in co-axial longitudinal alignment, as shown in FIGS. 2, 4, 5, and 6, as long as the force urging wedging member 11 and connector member 30 apart is greater than the tension of spring 17.

However, if any compressive force should be exerted across the apparatus, such as that encountered when a sudden surge of fluid causes the wireline tool suspended adjacent to the apparatus to move upward with respect to the wireline, the apparatus will move into the non-aligned, or wedging position, as shown in FIG. 1, thus ceasing the upward motion of the tool and any equipment suspended therewith.

The contact of planar faces 31 and gives this apparatus the advantage over the prior art of being very sensitive to small upward fluid surges exerted from below the tool in the production pipe. It also has the advantage of having no null point as do other tools in the prior art. The configuration of the apparatus is also beneficial in that, while under longitudinal tension, the tool aligns in a minimum lateral diameter for easy passage through the production pipe. The present embodiment also operates well even when completely submerged in the liquid within the production pipe.

Thus, it can be seen that a sensitive and reliable apparatus is shown for ceasing the upward movement of a wireline assembly caused by a sudden upward surge of pressure or fluid flow inside the pipe. Further modifications and alternative embodiments of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the manner of carrying out the invention. It is to be understood that the form of the invention herewith shown and described is to be taken as the presently preferred embodiment. Various changes may be made in the shape, size and arrangement of parts. For example, equivalent elements or materials may be substituted for those illustrated and described herein, parts may be reversed,

and certain features of the invention may be utilized independently of the use of other features, all as would be apparent to one skilled in the art afier having the benefit of this description of the invention. What is claimed is: 1. In a braking apparatus for use with a wireline tool in an annular opening, the combination comprising:

a wedging member having an oblique lower face; a connector member having a generally mating upper face which is oblique to the longitudinal axis of said apparatus; means for supporting said wedging member within said annular opening for travel of said apparatus therethrough; means for coupling said wedging member and said connector member, whereby relative convergent motion between said connector member and said wedging member wedges said wedging member between the side of said annular opening and said connector member by a sliding movement generally in a direction defined by the intersection of said mating oblique faces of said members, said coupling means comprising an elongate member which is generally aligned with the longitudinal axis of said apparatus when said apparatus is in the axially extended attitude and oblique to said longitudinal axis when said apparatus is in the wedging attitude;

means for supporting a tool from said connector member;

and, a spring joining said coupling means and one of said wedging member and said connector member biasing said wedging member and said connector member toward relative convergent motion.

2. In a braking apparatus for use with a wireline tool in an annular opening, the combination comprising:

a wedging member having an oblique lower face;

a connector member having a generally mating upper face which is oblique to the longitudinal axis of said apparatus;

a projection extending laterally from at least one of said wedging member and said connector member arranged for contacting the side of said wellbore when said apparatus is in the wedging attitude;

a projection shield extending laterally from at least one of said wedging member and said connector member arranged to limit abrasion to said projection when said apparatus is in the longitudinally extended attitude;

means for supporting said wedging member within said annular opening for travel of said apparatus therethrough;

means for coupling said wedging member and said connector member, whereby relative convergent motion between said connector member and said wedging member wedges said wedging member between the side of said annular opening and said connector member by a sliding movement generally in a direction defined by the intersection of said mating oblique faces of said members;

and, means for imparting relative convergent motion to said wedging member and said connector member when said apparatus is in an unloaded state. 

1. In a braking apparatus for use with a wireline tool in an annular opening, the combination comprising: a wedging member having an oblique lower face; a connector member having a generally mating upper face which is oblique to the longitudinal axis of said apparatus; means for supporting said wedging member within said annular opening for travel of said apparatus therethrough; means for coupling said wedging member and said connector member, whereby relative convergent motion between said connector member and said wedging member wedges said wedging member between the side of said annular opening and said connector member by a sliding movement generally in a direction defined by the intersection of said mating oblique faces of said members, said coupling means comprising an elongate member which is generally aligned with the longitudinal axis of said apparatus when said apparatus is in the axially extended attitude and oblique to said longitudinal axis when said apparatus is in the wedging attitude; means for supporting a tool from said connector member; and, a spring joining said coupling means and one of said wedging member and said connector member biasing said wedging member and said connector member toward relative convergent motion.
 2. In a braking apparatus for use with a wireline tool in an annular opening, the combination comprising: a wedging member having an oblique lower face; a connector member having a generally mating upper face which is oblique to the longitudinal axis of said apparatus; a projection extending laterally from at least one of said wedging member and said connector member arranged for contacting the side of said wellbore when said apparatus is in the wedging attitude; a projection shield extending laterally from at least one of said wedging member and said connector member arranged to limit abrasion to said projection when said apparatus is in the longitudinally extended attitude; means for supporting said wedging member within said annular opening for travel of said apparatus therethrough; means for coupling said wedging member and said connector member, whereby relative convergent motion between said connector member and said wedging member wedges said wedging member between the side of said annular opening and said connector member by a sliding movement generally in a direction defined by the intersection of said mating oblique faces of said members; and, means for imparting relative convergent motion to said wedging member and said connector member when said apparatus is in an unloaded state. 